drm/nvc0: implement channel structure initialisation

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/nouveau_object.c

@@ -779,6 +779,25 @@ nouveau_gpuobj_channel_init(struct nouveau_channel *chan,
 
 	NV_DEBUG(dev, "ch%d vram=0x%08x tt=0x%08x\n", chan->id, vram_h, tt_h);
 
+	if (dev_priv->card_type == NV_C0) {
+		struct nouveau_vm *vm = dev_priv->chan_vm;
+		struct nouveau_vm_pgd *vpgd;
+
+		ret = nouveau_gpuobj_new(dev, NULL, 4096, 0x1000, 0,
+					 &chan->ramin);
+		if (ret)
+			return ret;
+
+		nouveau_vm_ref(vm, &chan->vm, NULL);
+
+		vpgd = list_first_entry(&vm->pgd_list, struct nouveau_vm_pgd, head);
+		nv_wo32(chan->ramin, 0x0200, lower_32_bits(vpgd->obj->vinst));
+		nv_wo32(chan->ramin, 0x0204, upper_32_bits(vpgd->obj->vinst));
+		nv_wo32(chan->ramin, 0x0208, 0xffffffff);
+		nv_wo32(chan->ramin, 0x020c, 0x000000ff);
+		return 0;
+	}
+
 	/* Allocate a chunk of memory for per-channel object storage */
 	ret = nouveau_gpuobj_channel_init_pramin(chan);
 	if (ret) {
@@ -786,7 +805,7 @@ nouveau_gpuobj_channel_init(struct nouveau_channel *chan,
 		return ret;
 	}
 
-	/* NV50/NVC0 VM
+	/* NV50 VM
 	 *  - Allocate per-channel page-directory
 	 *  - Link with shared channel VM
 	 */
@@ -884,9 +903,6 @@ nouveau_gpuobj_channel_takedown(struct nouveau_channel *chan)
 
 	NV_DEBUG(dev, "ch%d\n", chan->id);
 
-	if (!chan->ramht)
-		return;
-
 	nouveau_ramht_ref(NULL, &chan->ramht, chan);
 
 	nouveau_vm_ref(NULL, &chan->vm, chan->vm_pd);